African Swine Fever

How to prevent ASFv getting onto pig farms

African Swine Fever (ASF) is slowly creeping towards western Europe, affecting mostly wild boar populations. It looks like the virus will not go away anytime soon. Which are the practical measure systems to minimise the risk of ASF entering a swine farm?

Physical isolation of the herd

Where possible, depending on the pig production system, isolation of a farm can be obtained by maintaining adequate distances between farms, by full fencing the herd and installing a closed entrance to the farm area.

Every visitor should be provided with specific clothes and footwear to be used and left on the farm. Photo: Henk Riswick

Introduction of new pigs into the herd

Only pigs from trusted and certified sources should be introduced into the herd;

Special attention should be given to the management of animal transport, and to the cleansing and disinfection procedures of the vehicles and the loading/unloading area;

The number of suppliers for replacement stock should be limited. The health status of replacement stock should be evaluated before purchase;

During the quarantine period, clinical surveillance should be combined with serological and virological surveillance, as appropriate.

In cleaning and disinfecting swine vehicles, attention should be given to the truck body and the loading ramp.

Disposal of carcasses

Vehicles collecting dead animals represent a major risk for the transmission of the disease. These vehicles should not enter the farm, and pig carcasses have to be collected outside the fence or premises. Drivers have to strictly follow farm biosecurity protocols and they should not enter the holding.

Carcasses of domestic pigs and wild boar found dead in the infected areas should be processed and tested to detect the presence of ASF virus. Carcasses, discarded parts from slaughtered pigs should be disposed by incineration or burial. No part of any wild boar should be brought into a pig holding.

Vehicles, clothing and footwear

Vehicles used for transport of pigs should be cleaned and disinfected immediately after each time transport of animals takes place, and if necessary before any new loading of animals using disinfectants, and provide documentary evidence that these operations have been performed.

In cleaning and disinfecting the vehicles, attention should be given to the truck body, the loading ramp, the equipment that had contact with pigs, the driver’s cabin and the protective clothes/boots used during unloading.

Drivers should follow farm biosecurity protocols when handling animals and, as a rule, they should not enter into pig holdings.

Workers and visitors

People entering the farm, including farmers and workers should not have been in contact with other pigs recently.

Every visitor should be provided with specific clothes and footwear to be used and left on the farm.

Slurry

Commercial pig holdings should be provided with storage basins, which allow manure treatment with disinfectants. Where necessary, the dispersion of pig slurry on agricultural lands should be avoided since the virus can be introduced into the environment infecting wild boar and free ranging pigs.

Genetic materials

To ensure that semen is free from the ASF virus, provisions and requirements provided in the EU legislation and by the World Organisation for Animal Health (OIE) should be followed.

Reducing direct pig‑to‑pig contact

The primary route of transmission of ASF is by direct contact between infected and susceptible pigs. Therefore, in risk areas it is necessary to adopt specific measures to minimise the risk of introducing the disease into the herd by direct contact, especially from wild pigs.

This article was compiled using a comprehensive review from 2016, authored by Italian scientists Silvia Bellini, Domenico Rutili and Vittorio Guberti, published in Acta Veterinaria Scandinavica.

Thank you for this article. It could be very useful here in China nowadays. I have one question. how to manage food supply for workers. Which is the safest way to be sure you will not bring a virus with vegetables and other kinds of meat? Here in China, they are using Virkon, glutaraldehyde, ozone for disinfection of vegetables for example.